The subject of the epistle: justification by grace; the
impossibility of uniting the law and the gospel

The epistle to the Galatians sets before us the great source of
the afflictions and conflicts of the apostle in the regions where
he had preached the glad tidings; that which was at the same time
the principal means employed by the enemy to corrupt the
gospel. God, it is true, in His love, has suited the gospel to the
wants of man. The enemy brings down that which still bears its
name to the level of the haughty will of man and the corruption of
the natural heart, turning Christianity into a religion that suits
that heart, in place of one that is the expression of the heart of
God -- an all-holy God -- and the revelation of that which He has
done in His love to bring us into communion with His holiness. We
see, at the same time, the connection between the judaising
doctrine -- which is the denial of full redemption, and looking
for good in flesh and man's will, power in man to work out
righteousness in himself for God -- in those who hindered the
apostle's work, and the attacks that were constantly aimed against
his ministry; because that ministry appealed directly to the power
of the Holy Ghost and to the immediate authority of a glorified
Christ, and set man as ruined, and Judaism which dealt with man,
wholly aside. In withstanding the efforts of the judaisers, the
apostle necessarily establishes the elementary principles of
justification by grace. Traces both of this combat with the spirit
of Judaism, by which Satan endeavoured to destroy true
Christianity, and of the maintenance by the apostle of this
liberty, and of the authority of his ministry, are found in a
multitude of passages in Corinthians, in Philippians, in
Colossians, in Timothy, and historically in the Acts. In Galatians
the two subjects are treated in a direct and formal way. But the
gospel is consequently reduced to its most simple elements, grace
to its most simple expression. But, with regard to the error, the
question is but the more decisively settled; the irreconcilable
difference between the two principles, Judaism and the gospel, is
the more strongly marked.

God allowed this invasion of His assembly in the earliest days
of its existence, in order that we might have the answer of divine
inspiration to these very principles, when they should be
developed in an established system which would claim submission
from the children of God as being the church that He had
established and the only ministry that He acknowledged. The
immediate source of true ministry, according to the gospel that
Paul preached to the Gentiles, the impossibility of uniting the
law and that gospel -- of binding up together subjection to its
ordinances and distinction of days -- with the holy and heavenly
liberty into which we are brought by a risen Christ, the
impossibility, I repeat, of uniting the religion of the flesh with
that of the Spirit, are plainly set forth in this epistle.